Appendix
0020300875_01 Energy
7
Installation and maintenance instructions
53
Fault code
Meaning
Possible cause
F.78
Interruption to DHW outlet sensor at
external control
UK link box is connected, but domestic hot water NTC not bridged
F.83
Fault: Dry fire
When the burner starts, the temperature change registered at the flow or
return temperature sensor is non-existent or too small: Insufficient water
in the product, the flow or return temperature sensor is not in the correct
position on the pipe
F.84
Fault: Flow/return temperature sensor
Values not consistent, difference < -6 K
Flow and return temperature sensors signalling implausible values: Flow and
return temperature sensors have been inverted, flow and return temperature
sensors have not been correctly installed
F.85
Fault: Temperature sensor
The flow and/or return temperature sensors have been installed on the same
pipe/incorrect pipe
Temperature sensor not connected or is connected incorrectly
F.86
Fault: Underfloor heating contact
Underfloor heating contact open, sensor disconnected or defective
F.87
Fault: Electrodes
Electrodes not connected or they are connected incorrectly, short circuit in
the cable harness
F.88
Fault: Gas valve assembly
Gas valve assembly not connected or it is connected incorrectly, short circuit
in the cable harness
F.89
Fault: Pump
Pump not connected or it is connected incorrectly, incorrect pump connec-
ted, short circuit in the cable harness
F.97
Fault: Main PCB self-test failed
Main PCB defective
Connection
No communication between the main
PCB and the user interface
Electronics defective